How is an S series switch process the Query message with the destination MAC address as the unicast MAC address

After Layer 2 multicast is enabled on a switch, the switch checks the destination MAC addresses of received IGMP messages. If the destination MAC address of a packet does not match its destination IP address, the switch drops the packet.
Therefore, when the switch receives IGMP Query messages with unicast destination MAC addresses, it drops the messages. As a result, user hosts cannot receive the Query messages, and multicast forwarding entries on the switch cannot be updated. Then multicast forwarding is interrupted.
When the switch connects to an ME60 and the ME60 performs multicast replication on a per user basis, IGMP Query messages sent from the ME60 uses user MAC addresses as destination MAC addresses. The switch drops these IGMP Query messages.
In this case, modify the configuration on the ME60 to ensure that the IGMP Query messages sent from the ME60 use destination MAC addresses mapping their destination IP addresses. Then the switch can generate a router port when receiving the Query messages and forward the Query message to user hosts.

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